The use of biomass in the second generation ethanol processes is known. A typical process will pre-treat the biomass with at least a steam explosion, hydrolyze the cellulose in the presence of enzymes and then ferment the resultant product to ethanol. A possible pre-treatment equipment setup with conceptual process steps is disclosed in WO 2009/108773. While WO 2009/108773 provides equipment, it provides no operational details for carrying out or treating the biomass.
The focus of past research has been to develop or select better enzymes to hydrolyze the cellulose so that the hydrolysis step can go faster. However, very little work or research has been done on treating the biomass in a manner so that it is more accessible to the enzymes. As it is known that the more accessible the material is before hydrolysis, the faster the hydrolysis reaction and less use of enzymes. There exists therefore, the need for a biomass feedstock which has higher enzyme accessibility than does previous forms of the biomass feedstock.